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1.
Cell Mol Life Sci ; 81(1): 73, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38308713

RESUMEN

N4 acetylcytidine (ac4C) modification mainly occurs on tRNA, rRNA, and mRNA, playing an important role in the expression of genetic information. However, it is still unclear whether microRNAs have undergone ac4C modification and their potential physiological and pathological functions. In this study, we identified that NAT10/THUMPD1 acetylates primary microRNAs (pri-miRNAs) with ac4C modification. Knockdown of NAT10 suppresses and augments the expression levels of mature miRNAs and pri-miRNAs, respectively. Molecular mechanism studies found that pri-miRNA ac4C promotes the processing of pri-miRNA into precursor miRNA (pre-miRNA) by enhancing the interaction of pri-miRNA and DGCR8, thereby increasing the biogenesis of mature miRNA. Knockdown of NAT10 attenuates the oncogenic characters of lung cancer cells by regulating miRNA production in cancers. Moreover, NAT10 is highly expressed in various clinical cancers and negatively correlated with poor prognosis. Thus, our results reveal that NAT10 plays a crucial role in cancer initiation and progression by modulating pri-miRNA ac4C to affect miRNA production, which would provide an attractive therapeutic strategy for cancers.


Asunto(s)
MicroARNs , Neoplasias , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Proteínas de Unión al ARN/metabolismo , Procesamiento Postranscripcional del ARN/genética , Citidina/genética , Neoplasias/genética
2.
J Biol Chem ; 299(7): 104851, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37220855

RESUMEN

Sphingosine 1-phosphate receptor 1 (S1PR1) is a G protein-coupled receptor essential for vascular development and postnatal vascular homeostasis. When exposed to sphingosine 1-phosphate (S1P) in the blood of ∼1 µM, S1PR1 in endothelial cells retains cell-surface localization, while lymphocyte S1PR1 shows almost complete internalization, suggesting the cell-surface retention of S1PR1 is endothelial cell specific. To identify regulating factors that function to retain S1PR1 on the endothelial cell surface, here we utilized an enzyme-catalyzed proximity labeling technique followed by proteomic analyses. We identified Filamin B (FLNB), an actin-binding protein involved in F-actin cross-linking, as a candidate regulating protein. We show FLNB knockdown by RNA interference induced massive internalization of S1PR1 into early endosomes, which was partially ligand dependent and required receptor phosphorylation. Further investigation showed FLNB was also important for the recycling of internalized S1PR1 back to the cell surface. FLNB knockdown did not affect the localization of S1PR3, another S1P receptor subtype expressed in endothelial cells, nor did it affect localization of ectopically expressed ß2-adrenergic receptor. Functionally, we show FLNB knockdown in endothelial cells impaired S1P-induced intracellular phosphorylation events and directed cell migration and enhancement of the vascular barrier. Taken together, our results demonstrate that FLNB is a novel regulator critical for S1PR1 cell-surface localization and thereby proper endothelial cell function.


Asunto(s)
Filaminas , Receptores de Esfingosina-1-Fosfato , Células Endoteliales/metabolismo , Filaminas/genética , Filaminas/metabolismo , Lisofosfolípidos/metabolismo , Proteómica , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo , Humanos , Técnicas de Silenciamiento del Gen , Células Cultivadas , Transporte de Proteínas
3.
Opt Express ; 32(9): 15370-15379, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859189

RESUMEN

A single-frequency distributed Bragg Reflector (DBR) fiber laser operating at 1091 nm was demonstrated by using a Yb:YAG crystal-derived silica fiber (YDSF). The YDSF was prepared via the molten core (MC) method, with a Yb2O3 doping concentration of 5.60 wt.% in the core, resulting in a gain coefficient of 1.45 dB/cm at 1091 nm. Employing 0.8 cm of the YDSF, we attained a single-frequency laser with a maximum output power of 145 mW and a slope efficiency of 31.8%. The laser exhibited an optical signal-to-noise ratio (OSNR) exceeding 71 dB, a linewidth of ∼34 kHz, and a stabilized relative intensity noise (RIN) at -132 dB/Hz for frequencies over 4.5 MHz. The fiber laser could serve as an outstanding seed source for high-power, narrow-linewidth fiber amplifiers operating at 1091 nm.

4.
Opt Express ; 32(3): 3974-3979, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297606

RESUMEN

We report on the continuous-wave (CW) and, for what we believe to be the first time, passively mode-locked (ML) laser operation of an Yb3+-doped YSr3(PO4)3 crystal. Utilizing a 976-nm spatially single-mode, fiber-coupled laser diode as pump source, the Yb:YSr3(PO4)3 laser delivers a maximum CW output power of 333 mW at 1045.8 nm with an optical efficiency of 55.7% and a slope efficiency of 60.9%. Employing a quartz-based Lyot filter, an impressive wavelength tuning range of 97 nm at the zero level was achieved in the CW regime, spanning from 1007 nm to 1104 nm. In the ML regime, incorporating a commercially available semiconductor saturable absorber mirror (SESAM) to initiate and maintain soliton-like pulse shaping, the Yb:YSr3(PO4)3 laser generated pulses as short as 61 fs at 1062.7 nm, with an average output power of 38 mW at a repetition rate of ∼66.7 MHz.

5.
Neuroradiology ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844696

RESUMEN

This retrospective study examined the clinical outcomes and complications in 6 cases of compound Meige's syndrome, presenting with blepharospasm and masticatory muscle spasm, following treatment with CT-guided radiofrequency ablation targeting bilateral facial nerves and mandibular branches of the trigeminal nerve. After the operation, the symptoms of eyelid spasm and masticatory muscle spasm resolved, but mild facial paralysis and numbness of mandibular nerve innervation persisted. Follow-up for 4-28 months showed that the symptoms of facial paralysis resolved within 2-5 (3.17 ± 0.94) months after the operation, whereas the numbness in the mandibular region persisted, accompanied by a decrease in masticatory function. During the follow-up period, none of the 6 patients experienced a recurrence of Meige's syndrome. These findings suggest that CT-guided radiofrequency ablation of the bilateral facial nerve and mandibular branches of the trigeminal nerve may offer a promising approach to treating compound Meige's syndrome.

6.
Appl Opt ; 63(1): 255-262, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38175028

RESUMEN

The development of optical tweezers aims to extend their operating function and pattern. However, excessive programming can lead to a decrease in the system's operating speed and introduce bugs or data transmission delays. In this study, we present a time-shared optical tweezers system that allows for parallel operation of multiple functions. To enable efficient data transmission, we employ a queue structure and a buffer. To assess the system's performance, we utilize a biological sample in conjunction with the optical tweezers system and scanning imaging technique. We quantify the trapping parameter while concurrently running power stabilization programs. As a result, the standard deviation of the measured stiffness is reduced by 60% in the x and y directions and 30% in the z direction, indicating a significant improvement in calibration precision. Throughout the program execution, the system maintains an operating rate of 110 kHz, and the data are continuously updated in real time on the host. The system's performance demonstrates its potential for quantification and morphological reconstruction of biological samples.

7.
J Am Chem Soc ; 145(1): 311-321, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36538760

RESUMEN

A unified strategy toward asymmetric divergent syntheses of nine C8-ethano-bridged diterpenoids A1-A9 (candol A, powerol, sicanadiol, epi-candol A, atisirene, ent-atisan-16α-ol, 4-decarboxy-4-methyl-GA12, trachinol, and ent-beyerane) has been developed based on late-stage transformations of common synthons having ent-kaurane and ent-trachylobane cores. The expeditious assembly of crucial advanced ent-kaurane- and ent-trachylobane-type building blocks is strategically explored through a regioselective and diastereoselective Fe-mediated hydrogen atom transfer (HAT) 6-exo-trig cyclization of the alkene/enone and 3-exo-trig cyclization of the alkene/ketone, showing the multi-reactivity of densely functionalized polycyclic substrates with πC═C and πC═O systems in HAT-initiated reactions. Following the rapid construction of five major structural skeletons (ent-kaurane-, ent-atisane-, ent-beyerane-, ent-trachylobane-, and ent-gibberellane-type), nine C8-ethano-bridged diterpenoids A1-A9 could be accessed in the longest linear 8 to 11 steps starting from readily available chiral γ-cyclogeraniol 1 and known chiral γ-substituted cyclohexenone 2, in which enantioselective total syntheses of candol A (A1, 8 steps), powerol (A2, 9 steps), sicanadiol (A3, 10 steps), epi-candol A (A4, 8 steps), ent-atisan-16α-ol (A6, 11 steps), and trachinol (A8, 10 steps) are achieved for the first time.


Asunto(s)
Diterpenos de Tipo Kaurano , Diterpenos
8.
J Am Chem Soc ; 145(16): 9233-9241, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37043290

RESUMEN

A new strategy focusing on the last-stage asymmetric assembly of the ring D, which inherently possesses the densest part of stereogenic centers and functional groups in the A/B/C/D ring system of (-)-cephalotaxine, has been developed, in which a novel Rh-catalyzed asymmetric (2 + 3) annulation of tertiary enamides with enoldiazoacetates is designed and explored for enantioselective construction of the crucial cyclopentane ring D bearing a unique spirocyclic aza-quaternary stereocenter. Based on the expeditious access of chiral functionalized building block with the tetracyclic A/B/C/D ring system, a concise enantioselective total synthesis of (-)-cephalotaxine starting from readily available homopiperonyl alcohol has been achieved in nine steps with only two column chromatography purifications. Following the tactical introduction of the Meinwald rearrangement, enantioselective divergent syntheses of (-)-cephalotine B with an additional C3-O-C11 oxo-bridged bond (14 steps), (-)-fortuneicyclidin B with an unprecedented C3-C10 bond (14 steps), and its 2-epimer (-)-fortuneicyclidin A (16 steps) have been also accomplished for the first time.

9.
Opt Lett ; 48(19): 5109-5112, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37773397

RESUMEN

A 1940 nm single-frequency distributed Bragg reflector (DBR) fiber laser was demonstrated based on a Tm : YAG/Ho : YAG-co-derived silica fiber (THCDSF). The THCDSF, which had a core dopant concentration of 8.02 wt.% Tm2O3 and 1.18 wt.% Ho2O3, was prepared via the melt-in-tube (MIT) method using a Tm : YAG and a Ho : YAG as the precursor core and a silica tube as the cladding. Employing 1.8 cm of the THCDSF, we achieved a maximum single-frequency output power of 315 mW at 1940 nm when pumped by a 1610 nm fiber laser. The slope efficiency of the laser was 29.68% for the absorbed pump power. The laser linewidth was less than 23.65 kHz, and the relative intensity noise (RIN) stabilized at -145 dB/Hz after exceeding 4.8 MHz. To the best of our knowledge, this is the first demonstration of a single-frequency DBR laser with a Tm3+/Ho3+ fiber as the gain medium.

10.
Pharmacol Res ; 191: 106773, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37068531

RESUMEN

Specific medications to combat cerebellar ataxias, a group of debilitating movement disorders characterized by difficulty with walking, balance and coordination, are still lacking. Notably, cerebellar microglial activation appears to be a common feature in different types of ataxic patients and rodent models. However, direct evidence that cerebellar microglial activation in vivo is sufficient to induce ataxia is still lacking. Here, by employing chemogenetic approaches to manipulate cerebellar microglia selectively and directly, we found that specific chemogenetic activation of microglia in the cerebellar vermis directly leads to ataxia symptoms in wild-type mice and aggravated ataxic motor deficits in 3-acetylpyridine (3-AP) mice, a classic mouse model of cerebellar ataxia. Mechanistically, cerebellar microglial proinflammatory activation induced by either chemogenetic M3D(Gq) stimulation or 3-AP modeling hyperexcites Purkinje cells (PCs), which consequently triggers ataxia. Blockade of microglia-derived TNF-α, one of the most important proinflammatory cytokines, attenuates the hyperactivity of PCs driven by microglia. Moreover, chemogenetic inhibition of cerebellar microglial activation or suppression of cerebellar microglial activation by PLX3397 and minocycline reduces the production of proinflammatory cytokines, including TNF-α, to effectively restore the overactivation of PCs and alleviate motor deficits in 3-AP mice. These results suggest that cerebellar microglial activation may aggravate the neuroinflammatory response and subsequently induce dysfunction of PCs, which in turn triggers ataxic motor deficits. Our findings thus reveal a causal relationship between proinflammatory activation of cerebellar microglia and ataxic motor symptoms, which may offer novel evidence for therapeutic intervention for cerebellar ataxias by targeting microglia and microglia-derived inflammatory mediators.


Asunto(s)
Ataxia Cerebelosa , Ratones , Animales , Ataxia Cerebelosa/inducido químicamente , Células de Purkinje/fisiología , Microglía , Factor de Necrosis Tumoral alfa/farmacología , Cerebelo , Citocinas
11.
Phys Chem Chem Phys ; 25(28): 19167-19174, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37431692

RESUMEN

The vertically stacked two-dimensional van der Waals heterostructure (2D vdWH) provides a unique platform for integrating distinctive properties of various 2D materials by functionalizing the interfacial interaction and regulating its band alignment. Herein, we theoretically propose a new MoSe2/Bi2O2Se vdWH material, in which a zigzag-zipper structure of the Bi2O2Se monolayer is constructed to model its ferroelectric polarization and maintain a small interlayer mismatch with MoSe2. The results show a typical unipolar barrier structure with a large band offset in the conduction band and nearly zero offset in the valence band of MoSe2/Bi2O2Se when the ferroelectric polarization of Bi2O2Se is back to MoSe2, in which the electron migration is blocked and holes can migrate unimpeded. It is also found that the band alignment lies between the type-I and type-II heterostructures and band offsets can be flexibly modulated under the joint action of ferroelectric polarization of Bi2O2Se and in-plane biaxial tensile and compressive strains. This work would facilitate the development of multifunctional devices based on the MoSe2/Bi2O2Se heterostructure material.

12.
Acta Pharmacol Sin ; 44(5): 969-983, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36807413

RESUMEN

Nuclear pore complex in the nuclear envelope plays an important role in controlling the transportation of RNAs, proteins and other macromolecules between the nucleus and cytoplasm. The relationship between abnormal expression of nucleoporins and cardiovascular diseases is unclear. In this study we investigated how myocardial infarction affected the expression and function of nucleoporins in cardiomyocytes. We separately knocked down 27 nucleoporins in rat primary myocardial cells. Among 27 nucleoporins, knockdown of Nup93, Nup210 and Nup214 markedly increased the expression of ANP and BNP, two molecular markers of cardiomyocyte function. We showed that Nup93 was significantly downregulated in hypoxic cardiomyocytes. Knockdown of Nup93 aggravated hypoxia-induced injury and cell death of cardiomyocytes, whereas overexpression of Nup93 led to the opposite effects. RNA-seq and bioinformatics analysis revealed that knockdown of Nup93 did not affect the overall transportation of mRNAs from the nucleus to the cytoplasm, but regulated the transcription of a large number of mRNAs in cardiomyocytes, which are mainly involved in oxidative phosphorylation and ribosome subunits. Most of the down-regulated genes by Nup93 knockdown overlapped with the genes whose promoters could be directly bound by Nup93. Among these genes, we demonstrated that Nup93 knockdown significantly down-regulated the expression of YAP1. Overexpression of YAP1 partially rescued the function of Nup93 knockdown and attenuated the effects of hypoxia on cell injury and cardiomyocyte death. We conclude that down-regulation of Nup93, at least partially, contributes to hypoxia-induced injury and cardiomyocyte death through abnormal interaction with the genome to dynamically regulate the transcription of YAP1 and other genes. These results reveal a new mechanism of Nup93 and might provide new therapeutic targets for the treatment of ischemia-induced heart failure.


Asunto(s)
Miocitos Cardíacos , Proteínas de Complejo Poro Nuclear , Animales , Ratas , Apoptosis , Regulación hacia Abajo , Hipoxia/metabolismo , Hipoxia/patología , Miocitos Cardíacos/metabolismo , Proteínas de Complejo Poro Nuclear/genética , Proteínas de Complejo Poro Nuclear/metabolismo , Transcripción Genética
13.
Nucleic Acids Res ; 49(5): 2859-2877, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33577677

RESUMEN

N 6-Methyladenosine (m6A) is the most abundant modification within diverse RNAs including mRNAs and lncRNAs and is regulated by a reversible process with important biological functions. Human YTH domain family 2 (YTHDF2) selectively recognized m6A-RNAs to regulate degradation. However, the possible regulation of YTHDF2 by protein post-translational modification remains unknown. Here, we show that YTHDF2 is SUMOylated in vivo and in vitro at the major site of K571, which can be induced by hypoxia while reduced by oxidative stress and SUMOylation inhibitors. SUMOylation of YTHDF2 has little impact on its ubiquitination and localization, but significantly increases its binding affinity of m6A-modified mRNAs and subsequently results in deregulated gene expressions which accounts for cancer progression. Moreover, Disease-free survival analysis of patients with lung adenocarcinoma derived from TCGA dataset reveals that higher expression of YTHDF2 together with higher expression of SUMO1 predicts poor prognosis. Our works uncover a new regulatory mechanism for YTHDF2 recognition of m6A-RNAs and highlight the importance of YTHDF2 SUMOylation in post-transcriptional gene expression regulation and cancer progression.


Asunto(s)
Adenosina/análogos & derivados , Neoplasias/metabolismo , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Sumoilación , Adenosina/metabolismo , Animales , Hipoxia de la Célula , Línea Celular , Progresión de la Enfermedad , Humanos , Lisina/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/genética , Neoplasias/patología , Estrés Oxidativo , Estabilidad del ARN , ARN Mensajero/química , Proteínas de Unión al ARN/química , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/antagonistas & inhibidores , Transcriptoma , Ubiquitinación
14.
Pediatr Emerg Care ; 39(6): 397-401, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37163676

RESUMEN

OBJECTIVES: Newborn deliveries and neonatal resuscitation events are rare but essential skills for pediatric emergency medicine (PEM) physicians. We sought to evaluate the effect of an online module on PEM physicians' knowledge and confidence in managing newborn deliveries and neonatal resuscitation. METHODS: A team of experts in PEM, obstetrics, neonatology, and medical education developed a self-directed, 1-hour online module on managing newborn deliveries with neonatal resuscitation. The module was designed to address the learning needs of the targeted group. The module was piloted before dissemination to PEM faculty. A 10-question multiple choice test was given to assess knowledge of the material covered. A 10-point Likert scale questions survey was used to evaluate confidence. Measures were administered before initiation, after module completion, and 6 months after completion. Paired t tests were used to compare mean knowledge scores, and rank sum tests were used to compare median confidence levels. RESULTS: Most (n = 47, 89%) of the PEM faculty members completed the module. The majority (n = 43, 91%) thought the information was relevant to their practice. After completing the module, physicians' overall knowledge scores improved by 18% (mean [SD]: 74% [14.7] vs 92% [8.0], P < 0.01). Self-assessed confidence improved after the module in terms of managing uncomplicated vaginal deliveries (median 5 vs 7, P < 0.01), care of patients with complicated vaginal deliveries (2 vs 5, P < 0.01), and managing neonatal resuscitation (7 vs 8, P < 0.01). During the 6-month follow-up, there was sustained improvement in physicians' overall knowledge score (82% [16.9], P = 0.007) and self-assessed confidence in managing complicated vaginal deliveries (median 2 vs 4, P = 0.0012); however, other measures were not statistically significant. CONCLUSIONS: An online module is an appropriate method for training PEM providers about rarely used but essential skills such as managing vaginal deliveries and neonatal resuscitation.


Asunto(s)
Medicina de Emergencia , Medicina de Urgencia Pediátrica , Médicos , Embarazo , Niño , Femenino , Recién Nacido , Humanos , Resucitación/educación , Aprendizaje , Servicio de Urgencia en Hospital , Medicina de Emergencia/educación
15.
Pediatr Emerg Care ; 39(3): 167-172, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36018727

RESUMEN

BACKGROUND: Several studies show that emergency medicine (EM) physicians are less comfortable caring for pediatric patients than adults. The state of pediatric training has not been comprehensively evaluated since 2000. OBJECTIVES: We sought to describe current pediatric education in EM residencies and to evaluate EM Program Director (PD) confidence in graduating trainees' abilities to care for pediatric patients. METHODS: We conducted an anonymous, cross-sectional survey study of EM PDs in August 2020. We collected program demographics, clinical rotations, and didactic methods. We used Likert scales to measure PD confidence in graduating residents' competence to care for pediatric and adult patients. RESULTS: We found e-mail addresses for 249 (93%) of 268 EM programs. One hundred nineteen (48%) PDs completed the survey. We include denominators to account for unanswered questions. Sixty-eight (59%) of 116 programs spend 10% to 20% of clinical time seeing pediatric patients. One hundred ten (91%) of 119 require a pediatric emergency medicine (PEM) rotation, 88/119 (83%) require pediatric intensive care, and 34/119 (29%) require neonatal intensive care. Seventy (62%) of 113 have curricula designed by PEM-trained faculty, 96/113 (85%) have PEM attendings teach lectures, and 77/113 (68%) spend 10% to 20% of didactic time on pediatric topics. Twenty-three (23%) of 106 PDs stated not all residents graduate with competence in pediatric resuscitation compared with 2/106 (2%) for adult resuscitation ( P < 0.05). CONCLUSIONS: Program directors report less confidence in graduating residents' competence in caring for pediatric patients compared with adult patients. We propose ideas to strengthen the quality of pediatric education in EM residencies.


Asunto(s)
Medicina de Emergencia , Internado y Residencia , Medicina de Urgencia Pediátrica , Adulto , Recién Nacido , Humanos , Niño , Medicina de Urgencia Pediátrica/educación , Estudios Transversales , Medicina de Emergencia/educación , Curriculum , Encuestas y Cuestionarios
16.
Sensors (Basel) ; 23(7)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37050504

RESUMEN

A resonant acoustic wave detector combined with Fabry-Pérot interference (FPI) and piezoelectric (PE) effects based on a polyvinylidene fluoride (PVDF) piezoelectric film was proposed to enhance the ability of the sensor to detect acoustic signals in a specific frequency band. The deformation of circular thin films was indicated by the interference and piezoelectric effects simultaneously, and the noise level was decreased by the real-time convolution of the two-way parallel signal. This study reveals that, at the film's resonance frequency, the minimum detection limits for the FPI and piezoelectric impacts on acoustic waves are 3.39 µPa/Hz1/2 and 20.8 µPa/Hz1/2, respectively. The convolution result shows that the background noise was reduced by 98.81% concerning the piezoelectric signal, and by 85.21% concerning the FPI signal. The convolution's signal-to-noise ratio (SNR) was several times greater than the other two signals at 10 mPa. Therefore, this resonance sensor, which the FPI and the piezoelectric effect synergistically enhance, can be applied to scenarios of acoustic wave detection in a specific frequency band and with ultrahigh sensitivity requirements.

17.
Sensors (Basel) ; 23(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36772317

RESUMEN

High temperature detection is a constant challenge for condition monitoring under harsh environments in optical fiber sensors research. In this study, the temperature response characteristics of guided acoustic wave Brillouin scattering (GAWBS) spectra in silica single-mode fiber (SMF) up to 800 °C are experimentally investigated, demonstrating the feasibility of the method for high-temperature monitoring. With increasing temperature, the resonance frequency of GAWBS spectra increases in a nearly linear manner, with linearly fitted temperature-dependent frequency shift coefficients of 8.19 kHz/°C for TR2,7 mode and 16.74 kHz/°C for R0,4 mode. More importantly, the linewidth of the GAWBS spectra is observed to narrow down with increasing temperature with a linearly fitted rate of -6.91 × 10-4/°C for TR2,7 modes and -8.56 × 10-4/°C for R0,4 modes. The signal-to-noise ratio of the GAWBS spectra induced by both modes increase by more than 3 dB when the temperature rises from 22 °C to 800 °C, which indicates that the proposed sensing scheme has better performance in high-temperature environments, and are particularly suitable for sensing applications in extreme environments. This study confirms the potential of high-temperature sensing using only GAWBS in silica fibers without any complex micromachining process, which has the advantages of strong mechanical strength, simple structure, easy operation, and low cost.

18.
Radiol Med ; 128(11): 1333-1346, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37740839

RESUMEN

OBJECTIVE: To investigate the diagnostic value of liver imaging reporting and data system (LI-RADS) v2018 and other imaging features in dual-phenotype hepatocellular carcinoma (DPHCC), establish a prediagnostic model based on gadoxetic acid-enhanced MRI, and explore the prognostic significance after surgery of the DPHCC. MATERIALS AND METHODS: Preoperative enhanced MRI findings and the clinical and pathological data of patients with surgically confirmed HCC were analysed retrospectively. Image analysis was based on LI-RADS v2018 and other image features. Univariate analysis was used to screen for predictive factors of DPHCC, and multivariate logistic regression analysis was used to determine the predictive factors. A regression diagnostic model was established. Receiver operating characteristic (ROC) curve analysis was used to determine the critical value, area under curve (AUC), and the corresponding 95% confidence interval (95% CI). The diagnostic performance was verified by fivefold cross-validation. Cox regression analysis was used to determine the prognostic factors associated with early recurrence after surgical resection. RESULTS: In total, 158 patients were included, of whom 79 had DPHCC and 79 had non-DPHCC. Multivariate analysis showed that rim arterial phase hyperenhancement (Rim APHE) and targetoid restriction were independent risk factors for DPHCC (P < 0.05). The AUC (95% CI) of the model was 0.862 (0.807-0.918), sensitivity was 81.01%, and specificity was 89.874%. Cox regression analysis showed that DPHCC, microvascular invasion, tumour diameter, and an increase of alpha-fetoprotein were independent factors for recurrence. CONCLUSION: Rim APHE and targetoid restriction were sensitive imaging features of DPHCC before surgery, and the identification of DPHCC has important prognostic significance for early recurrence.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Medios de Contraste , Gadolinio DTPA , Imagen por Resonancia Magnética/métodos , Fenotipo , Sensibilidad y Especificidad
19.
J Environ Manage ; 344: 118722, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37542864

RESUMEN

Identifying priority areas for conservation is an effective measurement for the sustainable provision of ecosystem services (ESs) under threats globally. Although many approaches have been developed to identify conservation priority areas by combining supply and demand of ESs, the integration of ESs flows into the identification still need further exploration. For ESs like freshwater supply services, the processes of freshwater flows across multiple scales are crucial. This study aimed to propose a new study framework to identify priority areas for freshwater supply conservation by integrating the multi-scale (i.e., sub-watershed, tributary, and mainstream) freshwater flows, using the Yangtze River Delta as the study area. The results suggested that spatial mismatches between the supply and demand of freshwater supply services existed at different scales. There were approximately 129, 58, and 55 pairs of freshwater flows in sub-watersheds, tributaries, and mainstreams, respectively, which transported 5.98 × 1010 m3, 2.07 × 1010 m3 and 2.50 × 1010 m3 of freshwater. The results of multi-scale freshwater flows were integrated into conservation target goals, and the identified priority areas for freshwater supply conservation were selected at three scales. The priority areas selected at the sub-watershed scale were the largest. Compared with the traditional method of identifying priority areas without considering freshwater flows, the priority areas identified in this study included both sites with a high supply capacity and sites with a relatively low supply capacity, as they were significant for meeting the local freshwater demand. The increasing understanding of freshwater flows and the integration of the flows for the identification of priority areas for freshwater supply conservation are important for the development of more practical and rational policies or ecological management for the sustainable conservation of ESs.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Agua Dulce , Ríos , China
20.
Sheng Li Xue Bao ; 75(5): 647-658, 2023 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-37909136

RESUMEN

A large number of studies have demonstrated that mRNA vaccine has been characterized as a technique with good safety, strong immunogenicity and high developmental potential, which makes it have broad prospects in immunotherapy. In recent years, the stability and in vivo delivery efficiency of mRNA vaccines have been largely addressed by the progresses in mRNA engineering and delivery innovation. And some mRNA vaccines are now clinical approved or in preclinical trials. Here, we summarize current knowledge on the research advances, technology, and application in major infectious diseases in humans and animals of mRNA vaccines, with the aim to provide a reference for improving the development of novel mRNA vaccines.


Asunto(s)
Enfermedades Transmisibles , Animales , Humanos , Vacunas Sintéticas/genética , Vacunas de ARNm
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